As well known by persons skilled in the art of collapsible ladders, such ladders usually comprise a number of tube portions having various diameters and which hence are telescopically insertable into one another. Every upper end of any of the tube portions are fastened to one end of a ladder step, whereas the other end of the ladder step is fastened to an upper end of a tube portion having the same diameter, the two tube portions and the ladder step forming a ladder section, the tube sections of which being insertable into an adjacent ladder section comprising tube portions having a larger diameter.
The resulting ladder can hence be collapsed by inserting higher ladder sections into lower ladder sections, and the ladder can be extended by extracting higher ladder sections from the lower ladder sections. A pin extending through the holes in the outer walls of two adjacent tube portions locks the tube portions to prevent the extended ladder from collapsing. Ladders having collapsible and expandable ladder sections are used in order to make the ladder smaller for storage and transport purposes.
The manufacturing process of a rung and the collapsible ladder to which will be attached involves several steps. Due to the construction of the rungs in prior art, the manufacturing and assembly process is complex. Furthermore, the durability of the collapsible ladder is always a quality that needs to be improved.
It is the object of the present invention to provide a rung and a collapsible ladder where the construction is simplified and the ladder is more durable.